Lab 5: Equine Reproduction

Question 1

Define azoospermia

Answer 1

absence of sperm in seminal fluid

Question 2

When clinically evaluating stallions, what should be the first step in determining if they are truly infertile

Answer 2

determining whether ejaculation is occuring

Question 3

List the 4 secondary signs of ejaculation

Answer 3

1 - flaggin the tail

2 - treading on hind feet

3 - strong urethral pulsations

4 - all followed by a dismount with the glands penis still fully or partially engorged

Question 4

What are 5 techniques that can be utilized if a stallion does not appear to be ejaculating?

Answer 4

1 - increase sexual stimulation

2 - evaluate internal and external genitalia for evidence of semen outflow obstruction

3 - evaluate hormonal characteristics

4 - perform biopsy

5 - evaluate testes, epididymis, and spermatic cords

Question 5

True or False: Secondary signs of ejaculation can occur without seminal emission.

Answer 5

True - retrograde ejaculation - sperm enters bladder instead of penis - still climax tho, just no semen

Question 6

How can producers, breeders, or veterinarians determine if ejaculation truly occurred in the stallion? Why?

Answer 6

Collecting and microscopically examining centrifuged urine sediment immediately after ejaculation

Question 7

If a stallion appears to be ejaculating, high or levels of ___ should first be measured to determine how to evaluate potential causes of infertility.

Answer 7

Alkaline phosphatase

Question 8

Match the possible diagnoses of stallions possessing small and soft testes with the age they would most likely appear.

Younger stallions have:

Older stallions have:

Answer 8

Younger stallions have: hypoplastic testes

Older stallions have: advanced testicular degeration

Question 9

If a stallion has undergone substantial testicular degeneration, how will the following hormones differ from normal circulating concentrations?

Estradiol

Inhibin

FSH

LH

Testosterone

Answer 9

Estradiol: decrease

Inhibin: decrease

FSH: increase

LH: increase

Testosterone: decrease

Question 10

Which organ is responsible for LH and FSH?

Answer 10

anterior pituitary

Question 11

___ may be indicated to assess the status of spermatogenesis in the stallion.

Answer 11

testicular biopsy

Question 12

The presence of what seminiferous tubule stage indicates spermatogenesis is proceeding to completion and that sperm are being released into the lumen?

Answer 12

Stabe VIII (8)

Question 13

What tool is commonly used to collect semen samples from a stallion?

Answer 13

artificial vagina

Question 14

For each of the six cases presented in the male case study, match the correct diagnosis.

(don’t know if you really need this or how they would ask)

Answer 14

1. bilateral epididymal hypoplasia
2. testicular degeneration
3. severe testicular degeneration
4. blockage of ampulla
5. bilateral segmental aplasia of vas deferens
6. infection and epididymitis

Question 15

Describe the appearance of the left and right ovaries of the 14-year-old mare in the female case study.

Answer 15

small right ovary and enlarged left ovary

Question 16

The presumptive diagnosis of the 14-year old mare was ___ cell tumor.

Answer 16

granulosa

Question 17

For granulosa cell tumors, what was the change in inhibin and progesterone concentrations?

Answer 17

inhibin: increase
progesterone: decrease

Question 18

What was the histological diagnosis of the mare’s ovary following biopsy?

Answer 18

granulosa-theca cell tumor

Question 19

True or False: The granulosa cell tumor is the least common ovarian tumor of mares.

Answer 19

Fale - The granulosa cell tumor is the most common ovarian tumor of mares.

Question 20

Inhibin performs negative feedback on ____ produced by the anterior pituitary gland.

Answer 20

FSH

Question 21

Why does follicular activity in the normal ovary without a granulosa cell tumor decrease?

Answer 21

The tumor produces large amounts of inhibin and this causes a reduction in FSH which decreases

Question 22

Define anestrus

Answer 22

no exhibition of any cyclic behavioral estrus